SlipX Solutions Adhesive Square Safety Treads Add Non-Slip Traction to Tubs, Showers & Other Slippery Spots - Design Your Own Pattern! (21 Count, Reliable Grip, Blue) A creative way to complement your bathroom dcor that provides reliable slip-resistance. Each package contains 21 square-shaped safety tread pieces. Easy to install and simple to clean. Tub tread piece diameters: 4.5", 3.25", 2". Designed for use on smooth surfaces. Some surface textures may affect adhesion. Not for use on refinished surfaces.